TRICHOTROPIS. 361 



simulate a rudimentary canal ; columella flattened, per- 

 forated. Operculum corneous, subconcentric, its nucleus 

 lateral. 



Animal with a short broad head, flanked by subulate 

 tentacles set wide apart, bearing the eyes at the extremities 

 of their thickened lower halves (or connate sustentacula) ; 

 mouth inferior, proboscis long, retractile, tongue with a 

 single series of hooked and serrated central denticles flanked 

 by three rows of curved laterals on each side, of which 

 the innermost only are serrated. Siphon scarcely exserted, 

 distinct ; margins of mantle simple, not reflected : foot 

 broad, quadrate in front, rounded but not produced behind. 



Of this very curious genus but few species are known, 

 and those yet discovered are natives of the Boreal Seas. 



T. BOREALis, Broderlp and Sowerby. 



Plate CI, fig. 5, 6, and (Animal) Plate II. fig. 1. 



Mttrex carinatus (not of Pennant), Laskey, Mem. Werner. Soc. vol. i. pi. 8, 

 f. 9 (copied by Brown, 111. Conch. G. B. pi. 5, f. 31, 32, 33) 

 probably. 

 Trichotropis borealis, Brod. and Sow. Zool. Joum. vol. iv. p. 375. — Maclaurin, 

 Berwick. Club, vol. ii. p. 40. — Alder, Cat. Moll. North- 

 umb. and Durh. p. 66. — Gould, Invert. Massach. p. 300, 

 f. 207. — Dekay, New York Moll. p. 137, pi. 8, f. 1 78. 

 — MiDDEN'n. Malac. Rossica, pt. 2, p. 108, 

 Fusvs umhilicatus. Smith, Mem. Werner. Soc. vol. viii. pt. 1, p. 98, pi. 1, f. 2. 

 Trichotropis costellafa, Couthouy, Boston Joum. N. H. vol. ii. p. 108, pi. 3, f. 2. 

 —Jay, Cat. Shells, ed. 2, p. 113, pi, 1, f. 17, 18. 

 „ acuminata, Jeffreys, Malacolog. Magaz. pt. 2, p. 36 (no descrip- 



tion).— Brown, Illust. Conch. G. B. p. 126, pi. 57, 

 f. 15, 

 „ Atlantica, Beck in Moller, Index Moll. Grcenl. p. 12, from types, 



„ conica, Mollek, Index Moll. Groenl. p. 12 (from description) pro- 



bably. 

 Fusus Laskeyi, Macgilliv. Moll, Aberdeen, p, 170. 



Trichotropis nmhilicatun, Macgilliv. Moll. Aberd. p. 330. — Brit. Marine Conch, 

 p. 209, f. 54. 



VOL. 111. 3 A 



